×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Welding Q125 Casing

Welding Q125 Casing

Welding Q125 Casing

(OP)
We are building a fixture for surface testing of downhole equipment. Our client has furnished two joints of 9-5/8 Q125 casing. The fixture requires that flanged be welded to the ends of the joints. We only need the strength of A36 plate at the welded joint. What is a recommended welding process to achieve a sound weld?

RE: Welding Q125 Casing

Shielded metal arc(SMAW) or stick welding process. Do you intend to use slip on flanges or butt welded flanges?

RE: Welding Q125 Casing

(OP)
I was thinking of beveling the end of the casing and then do V weld plus a fillet.

RE: Welding Q125 Casing

(OP)
Ho, the flange would be butt-weld type for just a flat plate.

RE: Welding Q125 Casing

(OP)
Sorry about the typing problem. My keyboard has sticky keys.

RE: Welding Q125 Casing

(OP)
Would you please recommend a weld wire or rod material and do we need to do any pre or post heat?

Thanks

RE: Welding Q125 Casing

You will need to get a chemical analysis of the casing to be sure. In all likelihood, you will need a preheat and most likely a post heat. If you cannot get a chemical analysis, assume it is 4140 and you won't crack it. You are likely to lower the strength of the Q125 a bit more than you need to, but it should still beat the heck out of A36.

What I would say, just knowing Q125, would be Preheat 500F. Post heat 1000F.
Q125 will likely be in the 0.30-0.35%C range, with perhaps 0.8-1.0% Cr. so cracking without any Preheat is likely. I'd postheat above 950F since it could well have Vanadium (~0.05) and Molybdenum (~0.15) since they need to hold 125PSI min yield and have impact strength.

RE: Welding Q125 Casing

I would strongly suggest you qualify a welding procedure using the above just to make sure you have no ductility issues with the Q125 in the weld region.

RE: Welding Q125 Casing

Quote:

I would strongly suggest you qualify a welding procedure using the above just to make sure you have no ductility issues with the Q125 in the weld region.
Absolutely!

RE: Welding Q125 Casing

API Committee never permitted welding on Q-125.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources